CMake: Further fine tune file -> target mapping
CMake: Further fine tune file -> target mapping

Instead of requiring that the target's source directory is a parent of
all source files, use a distance between the source and directory and
the file. This will find the wrong CMakeLists.txt in more cases but also
is much more likely to lead to using the fallback target.

This makes code completion work for http://github.com/dream3d/dream3d/

Change-Id: Ic035454c5eabe361bc7c46bd943e9a9cdee730e3
Reviewed-by: Tobias Hunger <012f8d714267bccc9d4766fbeace9f175fcc70c4@theqtcompany.com>

farseerri/git_code,martyone/sailfish-qtcreator,amyvmiwei/qt-creator,kuba1/qtcreator,kuba1/qtcreator,martyone/sailfish-qtcreator,amyvmiwei/qt-creator,kuba1/qtcreator,farseerri/git_code,danimo/qt-creator,danimo/qt-creator,AltarBeastiful/qt-creator,AltarBeastiful/qt-creator,kuba1/qtcreator,amyvmiwei/qt-creator,Distrotech/qtcreator,kuba1/qtcreator,martyone/sailfish-qtcreator,xianian/qt-creator,danimo/qt-creator,xianian/qt-creator,AltarBeastiful/qt-creator,martyone/sailfish-qtcreator,Distrotech/qtcreator,Distrotech/qtcreator,danimo/qt-creator,farseerri/git_code,danimo/qt-creator,martyone/sailfish-qtcreator,xianian/qt-creator,xianian/qt-creator,martyone/sailfish-qtcreator,Distrotech/qtcreator,xianian/qt-creator,AltarBeastiful/qt-creator,xianian/qt-creator,xianian/qt-creator,amyvmiwei/qt-creator,danimo/qt-creator,danimo/qt-creator,xianian/qt-creator,kuba1/qtcreator,farseerri/git_code,xianian/qt-creator,martyone/sailfish-qtcreator,amyvmiwei/qt-creator,amyvmiwei/qt-creator,Distrotech/qtcreator,Distrotech/qtcreator,Distrotech/qtcreator,amyvmiwei/qt-creator,danimo/qt-creator,AltarBeastiful/qt-creator,martyone/sailfish-qtcreator,AltarBeastiful/qt-creator,farseerri/git_code,martyone/sailfish-qtcreator,danimo/qt-creator,amyvmiwei/qt-creator,kuba1/qtcreator,farseerri/git_code,farseerri/git_code,AltarBeastiful/qt-creator,kuba1/qtcreator,farseerri/git_code,kuba1/qtcreator,AltarBeastiful/qt-creator